Niobium (V) halide/oxide-metal oxide compositions and a process for _their preparation

Abstract

Compositions are disclosed which comprise metal oxide substrates having niobium (V) halide(s)/oxide(s) bound to the surface thereof.

I claim: 
     
       1. A process for preparing a metal oxide substrate having a niobium (V) halide(s) bound to the surface thereof which process comprises subliming niobium pentahalide and reacting in a substantially anhydrous and oxygen-free atmosphere the vapor therefrom with a substantially anhydrous metal oxide substate having surface hydroxyl groups attached thereto. 
     
     
       2. The process of claim 1 wherein said metal oxide substrate contains a major portion of silica or alumina or a mixture thereof. 
     
     
       3. The process claims 1 or 2 wherein said halide is chloride, or a mixture thereof. 
     
     
       4. A process for preparing a metal oxide substrate having a mixture of niobium (V) chloride/oxide and niobium (V) fluoride/oxide bound to the surface thereof which process comprises: (a) subliming niobium pentachloride and reacting in a substantially anhydrous and oxygen-free atmosphere the vapor therefrom with a substantially anhydrous metal oxide substrate having surface hydroxyl groups attached thereto,   (b) contacting the product of step (a) with an oxygen-containing gas and   (c) contacting the product of step (b) with a liquid or gaseous fluorinated hydrocarbon.   
     
     
       5. The process of claim 4 wherein said metal oxide substrate has a major component of silica or alumina or a mixture thereof. 
     
     
       6. A composition comprising pentavalent niobium, halogen, oxygen and a metal oxide substrate wherein at least one valence of niobium is bound to oxygen which is bound to the substrate, at least one valence of the niobium is bound to halogen and the remaining niobium valences are bound to halogen and/or oxygen which may or may not be bound to the substrate wherein said halide is a mixture of chloride and fluoride and is prepared by a process which comprises: (a) reacting a substantially anhydrous, hydroxyl-containing metal oxide substrate with niobium pentachloride in the vapor state,   (b) contacting the product of step (a) with an oxygen-containing atmosphere and   (c) contacting the product of step (b) with a liquid or gaseous fluorinated hydrocarbon.   
     
     
       7. A composition comprising pentavalent niobium, halogen, oxygen and a metal oxide substrate wherein at least one valence of niobium is bound to oxygen which is bound to the substrate, at least one valence of the niobium is bound to halogen and the remaining niobium valences are bound to halogen and/or oxygen which may or may not be bound to the substrate wherein said halide is a mixture of chloride and fluoride and is prepared by a process which comprises: (a) subliming niobium pentachloride and reacting in a substantially anhydrous and oxygen-free atmosphere vapor therefrom with a substantially anhydrous, hydroxyl-containing metal oxide substrate,   (b) contacting the product of step (a) with an oxygen-containing atmosphere and   (c) contacting the product of step (b) with a liquid or gaseous fluorinated hydrocarbon.   
     
     
       8. The compositions of claims 6 or 7 wherein said metal oxide has a major component of silica, or alumina or mixtures thereof.